The present invention relates generally to a fluid filtering system commonly used to filter oil or fuel in diesel locomotive engines and, more particularly, to a fluid filtering system having a unique filter cartridge and associated support structure.
A typical oil or fuel filtering apparatus used in diesel locomotive engines has a filter housing into which one or more disposable filter cartridges are placed. The filter housing has apertures for the ingress and egress of fluid flowing through the housing. In the usual situation, each egress aperture has a small nozzle or spud inside the filter housing over which a filter cartridge is placed. The filter cartridges are typically secured in place over the spuds by either a retaining spider inside the housing or by the cover of the housing itself.
The filter cartridges are used for a specified period of time; after which the oil is drained, the filter housing cover is removed, the retaining spider (if applicable) is loosened and the cartridges are removed and replaced with new cartridges.
Typical disposable filter cartridges in the prior art have had rigid, usually metal, center-tubes (disposable) surrounded by an array of filtering material, with metal end-caps, and often with a perforated metal or paperboard exterior sheath. The use of metal components provides the filter cartridges with sufficient strength to withstand the high fluid pressures often reached during use.
In operation, these filter cartridges are placed within the filter housing such that the rigid perforated center-tube of each filter is placed over the spud of a fluid egress aperture and the retaining spider or housing cover is fit over the opposite end of the filter cartridges to secure them in place. The typical path of fluid flow is into the filter housing chamber, through the outside walls of the filter cartridges, through the filtering material, into their perforated center-tubes, and finally out of the filter housing through the fluid egress apertures. (Although this is a typical path of fluid flow, it could be reversed so that fluid flows from inside the filter cartridge out into the filter chamber.)
In the past, used filter cartridges were disposed of in any convenient manner. However, current and future environmental regulations will rigidly control how cartridges may be disposed. Spent cartridges are typically drained of oil and then either sent to an appropriate landfill as is or crushed to extract additional oil before going to the landfill. However, landfill space is becoming increasingly scarce--and expensive. Consequently, there is a desire to have a filter cartridge from which residual oil may be more thoroughly extracted and which may be disposed of by being incinerated.
While filter cartridges using metal parts function adequately for their intended purpose, problems have arisen with disposal of the used cartridges. The use of metal parts makes it difficult to compact the used filter cartridges in order to extract oil. Additionally the metal pieces (end-caps, center-tube, and, if applicable the exterior sheath) cannot be incinerated, thus making that method of disposal less effective.
Accordingly, it is a principal object of the present invention to provide a fluid filter cartridge which can be easily and effectively compacted for disposal.
A related object is to provide a fluid filter cartridge which can be completely incinerated.
It is another object of the present invention to provide an apparatus for conveniently adapting a fluid filter housing to accept coreless filter cartridges.
These objects, as well as others that will become apparent upon reference to the accompanying drawings and following detailed description, are provided by a coreless fluid filter cartridge made of non-metal parts, and apparatus for adapting a filter housing to support such coreless filter cartridges. A coreless filter cartridge has an elongate array of filtering material which defines an interior cavity. The array is surrounded by a sheath of perforated paper. Both ends of the array and sheath are embedded into polyurethane end-caps. The filter is secured in the filter housing by means of a rigid, perforated standpipe that has a bushing to fit over a fluid egress spud. The coreless filter cartridge is placed over the rigid standpipe and secured in place by the retaining spider or housing cover. A compression spring and compression cup are interposed between the coreless filter cartridge and retaining spider arm or housing cover to facilitate engagement. Gaskets on each end-cap prevent fluid by-pass and a stand-off cup is located near the base of the standpipe to provide a surface against which the end-cap gasket can seat.